西瓜柱头乳突细胞分泌活动期间ATP酶活性超微结构定位

研究了西瓜柱头乳突细胞ATP酶活性的超微结构定位。分泌活动旺盛的细胞中，质膜、内质网、质体的内部片层、胞间连丝以及多数大液泡的膜上面都有大量ATP 酶活性反应产物，线粒体和小泡上只有少量酶活性反应产物。分泌活动停止后处于解体状态的细胞内，反应产物主要定位于液泡膜上。分泌旺盛的乳突细胞质膜具有高的ATP酶活性表明分泌物运出需要大量能量，内质网 ATP 酶活性强可能意味着该细胞器参与分泌物合成。

Ultrastructural Localization of Adenosine Triphosphatase Activity in Watermelon Stigma Papilla Cells During Secretion

Adenosine triphosphatase activity in watermelon stigma papilla cells was studied. In cells with active secretion, enzyme reaction product was present in large quantities on the plasma membrane, vacuole membrane, plasmodesma and in the endoplasmic reticulum, plastid lamellae,and only in small quantities in the mitochondria and small vesicles.In cells which began degeneration and thus stopped secretion, enzyme reaction product was localized mainly on the vacuole membrane. The high adenosine triphosphatase activity on plasma membrane indicated that the transportation of secretion needs plenty of energy, and such enzyme activity in the endoplasmic reticulum may indicate that this organelle system is involved in the synthesis of secretion.